Aussie businessman kidnapped in Uganda

Ugandan police have warned the business community in Australia to be wary of African con men who promise lucrative oil deals after an Australian businessman was kidnapped and held for ransom.

Four Nigerians were later arrested for the crime.

Uganda police deputy spokesman Patrick Onyango said, "The Australian was the one who told us about his being kidnapped. The information we got from him helped us to arrest the kidnappers."

According to police, in mid-July 2013, at Madirisa zone on the outskirts of Uganda's capital Kampala, gangsters kidnapped an Australian and demanded a ransom of 650,000 euros ($A968,486).

They later settled for 350,000 euros, which the businessman's relatives paid before he was freed.

Mr Onyango said the businessman reported the kidnapping to police before boarding a plane for Australia.

"He did not want to get involved in the investigations. All he wanted was to return home. He flew back to Australia and left us to hunt for the thugs," Mr Onyango said.

The Department of Foreign Affairs and Trade said it recently provided consular assistance to a 61-year-old man in Uganda and to his family in Victoria.

Police said the arrested Nigerians were members of criminal cells operating in Uganda, Congo, Kenya and Liberia that lure foreigners into the country with fake deals, especially those involving oil.

When they were arrested, the suspects were found with documents carrying the forged signature of Uganda's President Yoweri Museveni and other fake agreements purportedly used to award contracts in the oil sector.

Mr Onyango said the Nigeria suspects were being held on charges of forgery, possession of government property, kidnap, aggravated trafficking and possession of counterfeit currencies.

He said two American businessmen were also kidnapped by the same group and were freed after a ransom was paid.